The Data Coordinating Center (DCC) for the Frequent Hemodialysis Network (FHN) will continue to coordinate the scientific and operational aspects of the two FHN clinical trials: one comparing short in-center 6x/week dialysis with conventional 3x/week dialysis and one comparing long home nocturnal 6x/week dialysis with home conventional 3x/week dialysis. During the on-going recruitment and follow-up of each FHN trial, the DCC will monitor patient recruitment and compliance as a whole and by clinical center. The database management system previously developed is used to assure accurate and complete collection of trial data. An inquiry system is used to resolve data discrepancies. The DCC will continue to make changes as necessary in the forms, database, manuals of operation, FHN web site, and reports. Many of the interactions with the clinical investigators are done through the work of subcommittees. The DCC will provide yearly centralized training of clinical center staff on the entry of trial patients, the completion of trial forms, and the use of the data management system. The DCC will promote adherence to the trial protocols. Site visit calls or visits to the clinical centers are made as necessary. Trial progress is given in reports to the clinical centers, Steering Committee, and Data Safety and Monitoring Board. Statistical analyses are performed during the course of each trial with final outcome analyses completed and reported at the end of each trial. The DCC handles the planning of meetings and conference calls, and administrative tasks. The DCC will develop new statistical methodology as needed to properly analyze the data being collected. Biological specimens and trial data (at end) are transferred to NIDDK repositories. Since the FHN is a multi-centered effort on two trials, the DCC will provide leadership to coordinate each trial's conduct to optimize resources and gain efficiencies. The DCC will work to foster a spirit of cooperation, which is important in this network. Results from the FHN trials will lead to a better understanding of more frequent hemodialysis beyond the conventional 3x/week and its impact on many outcomes affecting the health and well-being of hemodialysis patients.